LiDAR, which stands for Light Detection and Ranging, is an advanced remote sensing technique used to measure the surface of the earth. It utilizes pulsed infrared laser beams to measure distances and generate 3D information about the terrain and its characteristics.
A LiDAR point cloud is a set of data points representing 3D shapes or objects in a physical 3D space. They contain the most reliable 3D data possible.
.las is a file extension used for the Lidar Data Exchange Format, and is the file format used to store point cloud data. It contains information about each point collected, including x, y, and z coordinates, the classification of the point and the projection.
.laz is a file extension used for compressed lidar data. It is based on the same Lidar Data Exchange Format (LAS) as .las files, but the data is compressed to reduce the file size which allows lidar data to be stored more efficiently and transferred more quickly.
CRS, or Coordinate Reference System is a coordinate based system used to locate geographical locations on Earth. Examples include Mercator and UTM.
QGIS is a free, open-source Geographic Information System (GIS) created to view, edit, and analyze geospatial data.